Non-oriented magnetic steel sheets are used for various motors. For example, the non-oriented magnetic steel sheets are used for compressor motors of an air-conditioner and a refrigerator, and driving motors of an electric vehicle and a hybrid vehicle. The compressor motors of the air-conditioner and the refrigerator are mainly driven in an inverter mode, and therefore, reduction in core loss at a commercial frequency (50 Hz and 60 Hz) and reduction in core loss at a high frequency (100 Hz to 1000 Hz) are important to improve efficiency. A driving motor of an automobile changes a rotation speed in accordance with a traveling speed of the automobile. Besides, high motor torque is required when the automobile starts.
In consideration of the above, high magnetic flux density, low core loss at the commercial frequency, and low core loss at the high frequency (hereinafter, it is sometimes called a “high-frequency core loss”) are demanded for the non-oriented magnetic steel sheet. Further, a motor core is roughly classified into an integral type and a separate type, and the integral-type motor core is mainly used, and therefore, isotropic magnetic properties are demanded. However, a conventional non-oriented magnetic steel sheet cannot satisfy these requirements.